The invention relates to telecommunications and more particularly to an apparatus for permitting the attachment of a computer to an existing telephone system.
The incorporation of telecommunications capabilities into a Personal Computer (PC)xe2x80x94and particularly telephone functionsxe2x80x94is now widely generalized. This is generally achieved by means of a a modem which permits the attachment of the computer to a Public Switched Telecommunication Network (P.S.T.N.), thereby allowing data communications, for instance with an Internet Service Provider (ISP) which provides an access to the Internet network. The more recent modems allow sophisticated telephone facilities, such as voice announcement, voice recording, automated attendant and fax server and auto-dialing process.
However, the association of a personal computer with a modem for the access to a PSTN is not always possible.
First of all, it may well occur that the PC is not connected to any existing modem. In large organizations and entreprises, the computers are connected to a private network, such as a Local Area Network (L.A.N.) for instance, which provides communication facilities and connection to the outside world. For instance, the L.A.N. permits a direct access to the internet network, and permits the exchange of email messages. Any additional modem equipment would be largely superfluous in this environment.
Moreover, the connection of a modem equipment to a personal computer might even be impossible. This is a second situation where any modem attachment is impossible because the telephone network which is available is based on a proprietary integrated Private Automatic Branch Exchange (P.A.B.X.) offering service control and data functions. The PABX system may be generally provided with voice announcement, voice recording, automated attendant and fax server, DTMF digits collection capabilities, all of which provide powerful functions under control of the telephone set connected to the PABX system. Although these features are powerful, they are not easy to use because of the very poor user interface and interaction permitted by the classical telephone keyboard.
Thus in many situations, a personal computer cannot be connected to a PSTN via modem equipment and, therefore, cannot take advantage of the powerful facilities that the modem provides. In a large organization, a particular user is often equipped with both a telephone set and a personal computer, and the two pieces of equipment are unlikely to develop any kind of interaction with each other. It should be particularly noticed that the difficulty particularly results from the proprietary characteristics of the PABXxe2x80x94in terms of line impedance and voltage or phone signalingxe2x80x94that are used in the private PABX, and which differ from those of the Public Switch Telephone Network.
There is therefore a need for an improvement in the interaction between the personal computers and the telephone system, even when a proprietary line interface is considered. This is the condition of allowing new possibilities and enhancements in the interaction between the personal computer and the telephone network, and particularly taking advantage of the audio capabilities of the recent computers.
The technical problem to be solved by the present invention is to increase the interaction between a personal computer and the telephone system, in particular when no modem equipment is available, in order to take advantage of the multimedia possibilities that are offered by the computer.
The technical problem is solved by the present invention which is defined in the independent claim 1. Basically, there is provided an apparatus or adapter for attaching a personal computer PC comprising an audio system to a telephone network. The apparatus comprises a first connector for the connection to the base of a telephone set of a telephone system, a second connector for the attachment of a handset. When the apparatus and the personal computer are powered-off, the connection between the first connector and the second connector is maintained so that the handset can be directly used in association with the base of the telephone set. During power-on, the voice signal that is generated by the microphone of the handset is diverted by means of switching means, as well as the analog signal that is being produced by the audio system of the PC, and then transmitted to the remote party via the base of the telephone network.
This useful, simple and low cost arrangement allows the personal computer to get rid of any line interface requirements and to be well adapted to any kind of telephone system, since it takes advantage of the line interface. This is particularly useful in the case of a PABX since it is possible to use the line interface of the base equipment which is often supplied by the manufacturer of the PABX system.
In a preferred embodiment of the invention, the audio system of the PC is fitted with a headset (50) via a second analog channel, thus providing the possibility to use the headset as a hand-free phone external kit. Since the headset and the headphone can still be operated at the same time, the invention provides with the possibility of simple but effective two-person conference call at the same desk.
The invention is particularly adapted for the use of specific software running in the PC for producing DTMF control codes and more particularly audio files. This permits to enhance the ergonomy and the control of the complex features and facilities which are offered by modern PABX systems, such as voice message recording for instance, and which are normally controlled by means of the simple keyboard of the telephone set. The invention even allows the possibility to use efficient Graphic User Interface for controlling the basic functions of the PABX telephone systems, and thus increase the interaction between the latter and the personal computer.
More particularly, the invention renders possible the use of auto-dialing and voice server functions.